Typical video coding methods, to one degree or another, serve to reduce redundancies within a video sequence at the risk of introducing loss in the quality of the decoded video. Additionally, the resulting compressed bit stream is much more sensitive to bit errors. When transmitting the compressed video bit stream in an error-prone environment, such as the IP network, the decoder at the receive end of the communication link needs to be resilient in its ability to handle and mitigate the effects of these bit errors.
The Motion Picture Expert Group (MPEG) video encoding standards have has been widely adopted to transmit compressed video signals over band-limited channels in various multimedia applications, such as digital video broadcasting, which uses the MPEG-2 standard. The MPEG-2 standard is published as part of the International Standards Organization (ISO)/International Electrotechnical Commission (IEC) publication 13818, which is herein incorporated by reference.
The loss of an MPEG-2 transport stream (TS) packet results in the loss of one slice, two slices, or the entire frame (if the lost packet included the frame header), depending on the type of TS packet. Without a proper error concealment algorithm, the video quality created by an MPEG-2 video decoder will be severely degraded. To date, efforts at concealing the loss of an entire frame in an MPEG-2 video stream have been limited.